Simultaneous sampling of portal, hepatic and systemic blood during intragastric loading and tracer infusion in conscious pigs

A surgical model for catheterization at multiple sites has been developed for use in long-term metabolic studies. For blood sampling, catheters were inserted into the portal and hepatic veins and the common carotid artery. The hepatic vein catheter was inserted from the margin of a liver lobe and led through the venous system, until the tip was close to the bifurcation with the inferior vena cava. A new technique was developed to ensure correct placement of the hepatic vein catheter using the specific extraction of indocyanin-green over the liver during surgery. Gastrostomy was performed using a Pezzer catheter. Catheters in the artery and hepatic and portal veins were patent for blood withdrawal for up to 4 weeks, and thus allowed repeated metabolic studies. Studies were performed in conscious animals familiar with the experimental situation.     

老年颈内动脉系统急性脑梗死动脉溶栓的疗效观察

目的:探讨老年颈内动脉系统急性脑梗死动脉溶栓的疗效。方法:对我院老年科收治的63例老年颈内动脉系统急性脑梗死随机分为股动脉组以及颈动脉组,其中股动脉组患者30例,对其采用经皮股动脉穿刺微导管介入尿激酶溶栓治疗,颈动脉组患者33例,对其采用经皮患侧颈动脉穿刺尿激酶溶栓治疗。结果:对两组患者治疗前、术后2h以及术后30d采用NIHSS评分比较,两组患者NIHSS评分在术后2h及术后30d均较术前有明显改善(P<0.05);对两组患者治疗相关情况比较,股动脉组患者术后2h血管再通率明显高于颈动脉组(P<0.05),两组颅内出血率未显示出统计学差异性;对两组患者术后30d牛津残障OHS评分、BI指数比较,股动脉组患者明显优于颈动脉组(P<0.05)。结论:对老年急性脑梗死患者采用经皮股动脉穿刺微导管介入或采用经皮患侧颈动脉穿刺尿激酶溶栓治疗,均可有效改善患者预后,提高患者的临床疗效,两组相比较,股动脉组更能显示出优良的治疗率。     

The new era of cardiac surgery: hybrid therapy for cardiovascular disease

Surgical therapy for cardiovascular disease carries excellent long-term outcomes but it is relatively invasive. With the development of new devices and techniques, modern cardiovascular surgery is trending toward less invasive approaches, especially for patients at high risk for traditional open heart surgery. A hybrid strategy combines traditional surgical treatments performed in the operating room with treatments traditionally available only in the catheterization laboratory with the goal of offering patients the best available therapy for any set of cardiovascular diseases. Examples of hybrid procedures include hybrid coronary artery bypass grafting, hybrid valve surgery and percutaneous coronary intervention, hybrid endocardial and epicardial atrial fibrillation procedures, and hybrid coronary artery bypass grafting/carotid artery stenting. This multidisciplinary approach requires strong collaboration between cardiac surgeons, vascular surgeons, and interventional cardiologists to obtain optimal patient outcomes.     

彩色超声与盲探穿刺右颈内静脉并发症比较

目的比较彩色超声引导与盲探穿刺右侧颈内静脉置管术的并发症情况。方法将我院拟择期(在腹腔镜下)行结直肠肿瘤切除术的患者100例,ASA分级Ⅰ~Ⅲ级,年龄23~81岁,体重32~81kg。采用抛硬币法将患者随机分为彩色超声组(C)和盲探穿刺组(M)各50例。记录两组病人黑色细针试穿中静脉时次数、薄壁蓝空针穿刺中静脉时次数、穿刺点的数目、导管置入失败的次数,并记录病人由于穿刺引起的机械并发症及术后留置导管并发症情况。结果两组患者均未见明显机械并发症,且两组比较无统计学意义;两组无误穿动脉、血气胸及心律失常或心脏损伤的情况。结论彩色超声引导下行右颈内静脉穿刺成功率较盲探穿刺高,盲探穿刺刺破颈内静脉后壁概率较彩色多普勒超声引导下穿刺组高,其余机械并发症及留置中心静脉导管并发症比较无统计学意义。     

Minimally Invasive Monitoring of Chronic Central Venous Catheter Patency in Mice Using Digital Subtraction Angiography (DSA)

Background

Repetitive administration of medication or contrast agents is frequently performed in mice. The introduction of vascular access mini-ports (VAMP) for mice allows long-term vascular catheterization, hereby eliminating the need for repeated vessel puncture. With catheter occlusion being the most commonly reported complication of chronic jugular vein catheterization, we tested whether digital subtraction angiography (DSA) can be utilized to evaluate VAMP patency in mice.

Methods

Twenty-three mice underwent catheterization of the jugular vein and subcutaneous implantation of a VAMP. The VAMP was flushed every second day with 50 μL of heparinized saline solution (25 IU/ml). DSA was performed during injection of 100 μL of an iodine based contrast agent using an industrial X-ray inspection system intraoperatively, as well as 7±2 and 14±2 days post implantation.

Results

DSA allowed localization of catheter tip position, to rule out dislocation, kinking or occlusion of a microcatheter, and to evaluate parent vessel patency. In addition, we observed different ante- and retrograde collateral flow patterns in case of jugular vein occlusion. More exactly, 30% of animals showed parent vessel occlusion after 7±2 days in our setting. At this time point, nevertheless, all VAMPs verified intravascular contrast administration. After 14±2 days, intravascular contrast injection was verified in 70% of the implanted VAMPs, whereas at this point of time 5 animals had died or were sacrificed and in 2 mice parent vessel occlusion hampered intravascular contrast injection. Notably, no occlusion of the catheter itself was observed.

Conclusion

From our observations we conclude DSA to be a fast and valuable minimally invasive tool for investigation of catheter and parent vessel patency and for anatomical studies of collateral blood flow in animals as small as mice.     

Combined perfusion and percolation of embalmed animal bodies for removing formaldehyde

Excess formaldehyde was extracted from embalmed animal cadavers by vascular perfusion or combined perfusion and percolation with 20% ethanol. The perfusion was undertaken through a carotid artery and the percolation through the serous body cavities for 1-2 h. Nineteen goats were perfused once and one goat and three cows were perfused and percolated twice a day for 3 days. The extracted cadavers were stored in 20% ethanol or in a freezer at -20 degrees C. The mean value of the atmospheric concentration of formaldehyde after extraction was 0.27 +/- 0.05 mg/m3 for goats and 0.39 +/- 0.12 mg/m3 for cows.     

The two-headed swan

Pulmonary artery catheterization is a frequent procedure for hemodynamic monitoring in critically ill patients or high-risk surgical patients. Mechanical and infectious complications are recognized, though catheter dysfunction and malposition are more frequent and often require clinical intervention. We present the case of a Swan-Ganz catheter with the appearance of a mechanical fracture at the distal end, which required clinical and radiographic investigation to determine the nature of the aberrancy. The evaluation of a malfunctioning pulmonary artery catheter (PAC) is a frequent occurrence in the intensive care unit and requires careful clinical consideration and radiographic examination.     

超快速反应聚合物光纤氧测定装置及其用于活体动物机械通气下动脉血氧分压连续动态变化的初步实验报告*

目的: 我们在中国尝试使用超快反应聚合物光纤氧感受器置入整体活体动物动脉血管,再通过光电转换测定系统以记录活体动物颈动脉PO₂（PaO₂）连续动态的快速变化,为完善整体整合生理学理论体系中循环参与呼吸调控和呼吸循环代谢一体化调控提供实验依据。方法: ①超快反应氧感受器制作、性能及其测定系统标定：在实验室加热总长2 m光纤的远端5 mm部分,拉动直到它成锥形尖端,清洁并干燥后,将1 mm锥形光纤尖端浸涂到发光体掺杂聚合物溶液中,在溶剂快速蒸发同时将其缓慢抽出来形成氧气感测尖端,室温干燥24 h。对完成制作的感受器进行性能标定,并于第37日重复标定。②动物实验：在潍坊医学院实验室对山羊全麻气管插管氧气机械通气下,切皮暴露双颈动脉和左侧股动脉,分别把超快反应氧传感器直接插入动脉中,通过光导纤维、激发与检测Y型光纤耦合器经光电转换连接到个人电脑,实现机械通气下活体山羊颈动脉PaO₂的连续动态反应,主要分析PaO₂的呼吸间波浪式交替升降和肺-颈动脉时间延迟。结果: 该置入式超快反应氧传感器在液相的响应时间为100 ms。活体山羊实验40%~60%氧气机械通气心率和血压稳定,左和右颈动脉PaO₂随着呼吸机的吸气和呼气呈现波浪式上升和下降的呼吸交替现象,幅度高达15 mmHg;左侧股动脉位置记录的信息噪音显著干扰PaO₂变化。肺-颈动脉时间延迟是在吸气和呼气开始后1.5~1.7 s左侧和右侧颈动脉PaO₂都开始上升和下降;即肺通气开始后3次心跳,左心室可把肺毛细血管后动脉化的肺静脉血液送到外周化学感受器位置中断吸气切换为呼气和中断呼气切换为吸气,如此实现吸呼周而复始。结论: 活体动物置入动脉的超快反应氧传感器及其测定系统可测定PaO₂生理性波浪式变化,能为整体整合生理学医学新理论体系中解释吸气和呼气相互切换的机制提供实验依据。     

The analysis of glucose kinetics using a single jugular catheter in awake rats

The rates of glucose production and utilization can be estimated by a primed-constant infusion technique using separate catheters for the infusion of radiolabelled glucose and periodic blood withdrawal. In rats, a carotid artery catheter is most often combined with a jugular or femoral venous catheter in such studies. We presently describe a method which utilizes a single jugular catheter for both infusion and sampling in the awake rat. This method is directly compared with simultaneous carotid artery sampling during both the dynamic steady state and a nonsteady state induced by a constant infusion of insulin. Our results demonstrate the validity of a single vein design for the analysis of glucose kinetics in either state. Rapid sampling and complete flushing prevent disruption of infusate equilibrium and sample contamination respectively. This single catheter method requires less technical skill for placement, reduces surgical intervention and enhances the comfort of the awake rat.     

Coronary stenting using a 6 F. diagnostic catheter: a report of two cases

Standard guiding catheters for coronary interventions may not selectively engage the coronary ostium despite a successful cannulation with a diagnostic catheter of the same curve. This discrepancy is explained by a slight difference in shape between the two catheters (shorter tip of the guiding, absence of tip tapering, etc.). The authors report on the use of 6 F. coronary diagnostic catheters as guiding catheters for coronary angioplasty and stent implantation in two patients with critical stenoses: in the right coronary artery distal to a right internal mammary artery anastomosis in one and in the ostial right coronary artery in the other. In both cases, the use of diagnostic catheters was the key to success despite the vessel orifice being unfavourable for the use of different types of guiding catheters.     

Effect of oxytocin on plasma concentrations of 13,14-dihydro-15-keto-prostaglandin F2 alpha during the oestrous cycle and early pregnancy in the goat.

The effect of subcutaneous oxytocin on plasma concentrations of 13,14-dihydro-15-keto-prostaglandin (PG) F2 alpha (PGFM) was examined in the goat at various periods during the oestrous cycle and early pregnancy. 100 i.u. oxytocin was administered daily for 4 day, the dose being divided and given at 0900 and 2100 h; PGFM concentrations were assessed after the first treatment of each day. On days 3-6 (oestrus, day 0) PGFM concentrations increased significantly (P less than 0.001) within 15 minutes and both non-pregnant and mated goats exhibited oestrus behaviour by day 7. Significant (P less than 0.01) increases in PGFM were also produced on days 7-10, in both non-pregnant and pregnant goats, but the responses diminished from day 7 to day 10; only one goat (non-pregnant) came into oestrus. There was a marked difference in response between groups, however, during days 12-15. In non-pregnant goats significant (P less than 0.05) increases in PGFM were detected on days 13-15, but in pregnant animals oxytocin was without effect. Similarly, oxytocin did not increase PGFM concentrations on days 17-20 of pregnancy. However, uterine responsiveness reappeared in pregnant goats with significant (P less than 0.01) increases in PGFM on days 24 and 25.     

Use of intravenous abciximab as adjunctive therapy for carotid angioplasty and stent placement

The benefit of intravenous abciximab as an adjunctive to percutaneous coronary intervention has been demonstrated in large-scale randomized studies. The role of intravenous abciximab is being defined in carotid angioplasty and stent placement as the procedure is gaining popularity for the treatment of high-grade carotid stenosis in patients considered high-risk for carotid endarterectomy. This paper summarizes the pathophysiological basis and the available data for the use of abciximab as an adjunct to carotid artery stenting.     

Beta2-microglobulin knockout mice treated with anti-asialoGM1 exhibit improved hemodynamics and cardiac contractile function during acute intra-abdominal sepsis

We previously showed that beta2-microglobulin knockout mice treated with anti-asialoGM1 (beta2M/alphaAsGM1 mice) exhibit less hypothermia, reduced production of proinflammatory cytokines, less metabolic acidosis, and improved survival after cecal ligation and puncture (CLP) compared with wild-type mice. The present study was designed to assess hemodynamics and left ventricular contractility at 18 h after CLP. Arterial pressure was measured by carotid artery cannulation, and left ventricular pressure-volume loops were obtained by insertion of a 1.4-F conductance catheter into the left ventricle. Heart rate, stroke volume, and cardiac output were not significantly different between wild-type and beta2M/alphaAsGM1 mice after CLP. However, beta2M/alphaAsGM1 mice exhibited improved mean arterial pressure and systemic vascular resistance compared with wild-type mice. Myocardial function was also better preserved in beta2M/alphaAsGM1 mice as indicated by improved left ventricular pressure development over time, time-varying maximum elastance, endsystolic pressure-volume relationship, and preload recruitable stroke work. Overall, this study shows that cardiovascular collapse characterized by hypotension, myocardial depression, and low systemic vascular resistance occurs after CLP in wild-type mice. However, beta2M/alphaAsGM1 mice exhibit improved hemodynamics and cardiac contractile function after CLP that may account, in part, for our previously observed survival benefit.     

The distribution and clearances of hormones and metabolites in the circulation of the foetal sheep.

Plasma hormone and metabolite concentrations have been measured in the plasma of blood collected simultaneously from the femoral artery, umbilical vein and carotid artery of the exteriorized foetal sheep. The concentration of vasopressin and catecholamines was consistently lower and of glucose, lactate and corticosteroids consistently higher in the umbilical vein compared with the femoral artery. ACTH concentrations showed no consistent pattern and fluctuated widely at each site, but during synacthen infusion the concentration in the umbilical vein was consistently lower than in the femoral artery. For corticosteroids the concentration in the carotid artery was much lower than that in the umbilical vein; the converse was true for catecholamines. Concentrations in the carotid and femoral artery were similar for all compounds investigated. These results indicate that the placenta is a major site of vasopressin, catecholamine and ACTH clearance and of glucose, lactate and corticosteroid production. The foetal liver is probably a major site of corticosteroid and catecholamine clearance.     

Shearing at the end of summer affects body temperature of free-living Angora goats ( Capra aegagrus) more than does shearing at the end of winter

Angora goats are known to be vulnerable to cold stress, especially after shearing, but their thermoregulatory responses to shearing have not been measured. We recorded activity, and abdominal and subcutaneous temperatures, for 10 days pre-shearing and post-shearing, in 10 Angora goats inhabiting the succulent thicket of the Eastern Cape, South Africa, in both March (late summer) and September (late winter). Within each season, environmental conditions were similar pre-shearing and post-shearing, but September was an average 5°C colder than March. Shearing resulted in a decreased mean (P < 0.0001), minimum (P < 0.0001) and maximum daily abdominal temperature (P < 0.0001). Paradoxically, the decrease in daily mean (P = 0.03) and maximum (P = 0.01) abdominal temperatures, from pre-shearing to post-shearing, was greater in March than in September. Daily amplitude of body temperature rhythm (P < 0.0001) and the maximum rate of abdominal temperature rise (P < 0.0001) increased from pre-shearing to post-shearing, resulting in an earlier diurnal peak in abdominal temperature (P = 0.001) post-shearing. These changes in amplitude, rate of abdominal temperature rise and time of diurnal peak in abdominal temperature suggest that the goats' thermoregulatory system was more labile after shearing. Mean daily subcutaneous temperatures also decreased post-shearing (P < 0.0001), despite our index goat selecting more stable microclimates after shearing in March (P = 0.03). Following shearing, there was an increased difference between abdominal and subcutaneous temperatures (P < 0.0001) at night, suggesting that the goats used peripheral vasoconstriction to limit heat loss. In addition to these temperature changes, mean daily activity increased nearly two-fold after March shearing, but not September shearing. This increased activity after March shearing was likely the result of an increased foraging time, food intake and metabolic rate, as suggested by the increased water influx (P = 0.0008). Thus, Angora goats entered a heat conservation mode after shearing in both March and September. That the transition from the fleeced to the shorn state had greater thermoregulatory consequences in March than in September may provide a mechanistic explanation for Angora goats' vulnerability to cold in summer.     

Comparative study on seasonal hair follicle cycling by analysis of the transcriptomes from cashmere and milk goats

Guard hair and cashmere undercoat are developed from primary and secondary hair follicle, respectively. Little is known about the gene expression differences between primary and secondary hair follicle cycling. In this study, we obtained RNA-seq data from cashmere and milk goats grown at four different seasons. We studied the differentially expressed genes (DEGs) during the yearly hair follicle cycling, and between cashmere and milk goats. WNT, NOTCH, MAPK, BMP, TGFβ and Hedgehog signaling pathways were involved in hair follicle cycling in both cashmere and milk goat. However, Milk goat DEGs between different months were significantly more than cashmere goat DEGs, with the largest difference being identified in December. Some expression dynamics were confirmed by quantitative PCR and western blot, and immunohistochemistry. This study offers new information sources related to hair follicle cycling in milk and cashmere goats, which could be applicable to improve the wool production and quality.     

贵州地方山羊品种的RAPD分析

用180条引物对黔东南小香羊、贵州白山羊、贵州黑山羊和黔北麻羊4个贵州地方山羊品种(种群),以及南江黄羊和波尔山羊进行RAPD分析,其中27条引物扩增出多态性图谱。这27条引物共扩增出281条带,多态带为115条,平均多态频率为40．92％(范围20％～80％);每条引物平均扩增条带为10．41条(范围4～16条);扩增带分子量在210～2800bp。贵州白山羊与贵州黑山羊之间的遗传距离指数(0．0605)最小,而波尔山羊与其他品种之间的遗传距离指数(0．1059～0．1488)最大。NJ法聚类结果显示,贵州白山羊与贵州黑山羊间的亲缘关系最近,其次为黔北麻羊,而黔东南小香羊与其他3个贵州地方品种的亲缘关系较南江黄羊还远。分析表明,黔东南小香羊在遗传上为一独立的品种;而贵州地方山羊品种间具有较近的亲缘关系,遗传变异较小,具有较高的遗传稳定性。     

Distribution of [3H]dexamethasone in rat subcutaneous tissue after delivery from osmotic pumps

Inflammation surrounding implantable glucose sensors may be controlled through local release of dexamethasone at the site of implantation. In the present study, we evaluated the distribution of dexamethasone in rat subcutaneous tissue during the first 2.5 days after local release. Osmotic pumps containing [3H]dexamethasone were implanted into the subcutaneous tissue of rats. Digital autoradiography was used to measure the distribution of the [3H]dexamethasone within the subcutaneous tissue at 6, 24, and 60 h after implantation. Measured concentration profiles, near the catheter tip through which the agent was released, were compared to mathematical models of drug diffusion and elimination. The results demonstrate that the majority of the [3H]dexamethasone delivered into the subcutaneous tissue was found within a 3 mm region surrounding the catheter tip. There was good agreement between the experimental data and the mathematical model. The diffusion coefficient for dexamethasone in subcutaneous tissue was found to be D = 4.11 +/- 1.77 x 10(-10) m2/s, and the elimination rate constant was found to be k = 3.65 +/- 2.24 x 10(-5) s(-1). The diffusion coefficient and elimination rate constants for dexamethasone in subcutaneous tissue have not been previously reported. The use of a mathematical model may be useful in predicting the effectiveness of local delivery of dexamethasone around implantable glucose sensors.     

A reevaluation of rabbit anti-allotype antibody for the presence of cross-reactive idiotypes. II. Expression of rabbit a1-like images on goat antibody after immunization with anti-a1 antibody

In an effort to generate heterologous anti-idiotype (Ab2) molecules to a suspected IdX on rabbit anti-a1 antibody (Ab1), goats were immunized with either rabbit or guinea pig Ab1. The goat Ab2 preparations reacted with each of 13 rabbit Ab1, as well as two goat Ab1 samples in serologic assays. From 8 to 50% of the molecules in purified rabbit Ab1 preparations reacted with each goat Ab2. Electron microscopy of immune complexes composed of rabbit Fab anti-a1 and goat Ab2 reveals that the Fab anti-a1 binds to the side of the variable region of most goat Ab2 molecules, rather than at the tip (i.e. in the CDR) as expected. This configuration indicates that the goat Ab2 actually represents a population of induced or enhanced Ig molecules expressing a1-like allotypic or isotypic determinants, rather than an anti-IdX Ab or a paratope-associated internal image of a1.